Solar Panel Differences?? Teach Me!!

So - I have a location where I can fit either of these solar panels (but not anything larger), but just wondering, why is there a big discrepencey between the two specs of these units? They are approximately the same size - I am a newb on this stuff, so and help is appreciated - but I always though size was important in solar panels.

Right, but I can't fit the 60 watt panel that AT sells! I need to know about these two.

How can two panels of approximately the same size produce far different specifications?

Also, why is one 50% of the other in cost? I imagine the higher cost one uses a different technology that improves power generation, but is it real? Or just smoke and mirrors from flawed testing, or marketing hype?

Picking obscure items from amazon and asking about prices isn't asking an answerable question. Or rather the answer is that they cost what they do because that's what the seller decided.
The link above is to Sun Electronics, a major discounter. All the panels they sell are from major suppliers. Pick a panel with a Vmp of 15-18, pick an appropriate size inexpensive Morningstar or Blue Sky controller, talk to the vendor about wire and mounting and you're done. (Blue Sky you would need to buy elsewhere).

Of the 2 you mention, the Brunton won't do much more than trickle charge your batteries. It doesn't have enough power to run the Engel.

Big difference between 80 watt and 15 watt panels, even though similar in size.

What is the size of the space you have available? With that, I can help better with a panel.

Also, might want to consider some of the portable suitcase style panels out there now.
80 watt ones are priced pretty reasonable and include a charge controller.
Many to choose from, most made in China so have to be careful on the quality.
Able to be placed where the sun is without having your rig in the sun.

crystalline silicon (c-Si) vs. amorphous thin film silicon (a-Si TFPV): much higher watts per unit area is the difference you're seeing.
For mobile application, you pretty much want to stick with c-Si since space is at a premium. Some people like the roll-up CIGS cells which fall somewhere in between c-Si and a-Si...but price is quite high.
Sanyo, Kyocera, Sharp are some of the best c-Si panels, though they do not make very low-wattage panels...maybe 40W at a minimum? Yeah, check for Kyocera KC40T...it's a pricey but high-quality panel..$200-$300.
Also, better panels will have better weather sealing and less power drop over the life of the cell compared to most Chinese manufactured panels.
Having said all that, do your DD...I suggest at least a few hours research for every $100 you plan to spend.
Good luck!